Lock ring volume

[Gabriel.Syr]

Hi, i want to lock the ring volume level to avoid the user to turn off the ring sound.

I tried editing this parameter (in bold):

[ Volume ]
nToneHandfree = 4 to 12
nToneHandset = 4 to 12
nToneHeadset = 4 to 12
nTalkOutputHandfree = 15
nTalkOutputHandset = 8
nTalkOutputHeadset = 8
nTalkInputHandfree = 5
nTalkInputHandset = 5
nTalkInputHeadset = 5
nRing = 4
nColorRingback = 3
bButtonSoundOn = 1
bSendKeySoundOn = 1


But i need a way to make this parameter read only.

Can you help me? is for a Yealink t19P